I fly to the mountains where they live and choose my argie. Then u have to fly close to it with a ptera and maybe hit it quickly. I recommend pressing k so that u can see where it is. If u fly very close to it and maybe even let it hit u once every now and then it will follow u over the entire map without losing aggro even once. If youre close to your base whistle all your tames passive (since u cant sprint with the ptera because u would otherwise fly ahead to much even a low lvl should have more then enough stamina to not even land once), land your ptera and start firing tranq arrows at it. It will try to fly off if youre 1 arrow away frome tranqing it, but since they fly very slow u should be able to hit it without any problems (aslong as u dont have parkinson and no arms) and it should land very close to your base.

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